SEAL AS 8T1789 - Caterpillar

Removal Procedure
Table 1
Required Tools
Tool Part Number Part Description Qty
A 230-6284 Timing Pin (Camshaft) 1
B 230-6283 Timing Pin (Crankshaft) 1 Start By:
Remove the fuel injection pump gear. Refer to Disassembly and Assembly, "Fuel Injection Pump - Remove".
Remove the valve mechanism cover. Refer to Disassembly and Assembly, "Valve Mechanism Cover - Remove and Install". Note: Care must be taken in order to ensure that the fuel injection pump timing is not lost during the removal of the fuel pump gear. Carefully follow the procedure in order to remove the fuel pump gear.
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Illustration 1 g01343975
Alignment of timing marks
Ensure that Tooling (A) is installed into hole (X) in the camshaft gear. Use Tooling (A) in order to lock the camshaft in the correct position. Note: Ensure that the gears are marked in order to show alignment. Refer to Illustration 1.
Ensure that Tooling (B) is installed in hole (Y) in the front housing. Use Tooling (B) in order to lock the crankshaft in the correct position.
Illustration 2 g01348926
Typical example
Loosen nuts (4) on all rocker arms (5). Unscrew adjusters (3) on all rocker arms (5) until all valves are fully closed. Note: Failure to ensure that ALL adjusters are fully unscrewed can result in contact between the valves and pistons.
Mark plate (3) in order to show orientation. Refer to Illustration 1. Note: Identification will ensure that the plate can be installed in the original orientation.
Remove bolts (1). Refer to Illustration 1.
Remove plate (3).
Illustration 3 g01269930
Typical example
Remove the assembly of idler gear (2) and hub (7) from the recess in the front housing. Note: The idler gear must be tilted during removal.
Remove hub (7) from idler gear (2). Installation Procedure
Table 2
Required Tools
Tool Part Number Part Description Qty
A 230-6284 Timing Pin (Camshaft) 1
B 230-6283 Timing Pin (Crankshaft) 1
C 9U-7324 Indicator Bracket 1
7H-1942 Dial Indicator 1
3S-3268 Indicator Contact Point 1
7H-1940 Universal Attachment 1
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Ensure that number one piston is at the top center position on the compression stroke. Refer to the Systems Operation, Testing and Adjusting, "Finding Top Center Postion for No. 1 Piston".
Illustration 4 g01343975
Alignment of timing marks
Ensure that Tooling (A) is installed into hole (X) in camshaft gear (1).
Ensure that Tooling (B) is installed in hole (Y) in the front housing. Use Tooling (B) in order to lock the crankshaft in the correct position. Refer to Systems Operation, Testing and Adjusting, "Finding Top Center Position for No.1 Piston".
Illustration 5 g01269934
Clean idler gear (2) and inspect the idler gear for wear or damage. Refer to Specifications, "Gear Group (Front)" for more information. If necessary, replace the idler gear.
Clean hub (7) and inspect the hub for wear or damage. Refer to Specifications, "Gear Group (Front)" for more information. If necessary, replace the hub.
Lubricate hub (7) with clean engine oil. Slide the hub into idler gear (2). Ensure that the timing marks are toward the